System and method for distributed navigation service

ABSTRACT

A distributed navigation system and method for providing driving instructions to a user. The system includes a service center having a navigation server and associated workstations. The service center stores driving instructions in a continuously updated map database. In response to a user request the instructions are transmitted by way of a wireless network to a client device residing in the user vehicle. The instructions are assembled into sequential stepwise driving directions and stored in a storage device in the client device. Commands from the user trigger playback of the driving instructions in a stepwise fashion.

FIELD OF THE INVENTION

[0001] The present invention generally relates to the field ofnavigation systems for automotive vehicles. More particularly, theinvention is directed to a system for providing driving directions to auser and a method of operating the system.

BACKGROUND OF INVENTION

[0002] Vehicle operators need the ability to obtain accurate navigatingdirections from a current position without the difficulties of beingconnected to a service operator via a phone call. For example, being incontinuous phone connection with an operator may contribute to reducedattentiveness to driving conditions. Likewise, operators at servicecenters need a system to quickly analyze the driver's vehicle positionto deploy relevant and accurate directions in the shortest timepossible.

[0003] A number of navigation systems exist that provide drivinginstructions to a user or operator of a motor vehicle. In general, thesesystems fall into two categories: autonomous or stand-alone systems, andsystems that involve a communication link to a server or human operator.

[0004] Most autonomous systems are relatively high-cost devices that aredesigned to be permanently installed into a vehicle. The devices includemap information, typically stored on a CD-ROM, and a means to relay thatinformation to a user in speech or images. Typically, these systemsutilize a device to determine the position of the vehicle. Many currentvehicle navigation systems use a Global Positioning System (GPS). GPSincludes NAVSTAR GPS and its successors, Differential GPS (DGPS), or anyother electromagnetic wave positioning system. Such a GPS system can beused to calculate distance and direction traveled. Other systems used tocalculate vehicle position include various sensors attached to thevehicle to measure the progress of the vehicle relative to a previouslyknown position. This method of dead reckoning, however, is susceptibleto sensor error, and therefore requires expensive sensors for accuracyand dependability.

[0005] Many types of on-board vehicle navigation apparatus having theability to give navigational instructions in speech form have beensuggested for the driver's convenience. With these types of on-boardsystems with oral navigation functions, a route from the currentposition to the destination is automatically determined based on the mapdata once the driver specifies the desired destination. When the vehicleapproaches an intersection while traveling along the suggested route, anoral navigational instruction is given as to whether to turn right orleft at the intersection.

[0006] Another example of an autonomous system includes theimplementation of a database and navigation system based on a laptopcomputer platform. This system includes a GPS unit for providing aposition of the laptop computer. Driving instructions are provided by atext to voice converter that converts the text driving instructions intoa voice signal. The instructions are output by the computer at a timebased on the position of the vehicle and a time period required to speakthe directions.

[0007] Other prior art systems include a wireless communication devicewith which a vehicle occupant retrieves driving instructions from aservice representative or operator. In such a system, however, theoperator does not have a system to quickly analyze the vehicle position.Further, either the operator must stay in voice contact with the vehicleuser to continuously relay instructions to the user or the user mustrecord the directions and then refer to them. However, reference to therecorded directions during driving may contribute to a dangerous drivingsituation.

[0008] Accordingly, it would be desirable to have a relatively low-costnavigation system whereby the operator of a vehicle could obtain andrefer to accurate directions in a convenient format that overcomes thedisadvantages described above. In particular, one embodiment of themethod and system of the present invention provides vehicle operatorsthe ability to obtain accurate driving directions from a current drivinglocation by downloading up-to-date route information from acomputer-based server in an audible format and output in response tovoice commands.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009]FIG. 1 is a block diagram of an embodiment of a navigation systemof the present invention;

[0010]FIG. 2 is a block diagram of an embodiment of the client device ofthe present invention;

[0011]FIG. 3 is a flow chart of an embodiment of the method of operationof the present invention; and

[0012]FIG. 4 is a flow chart of the embodiment continued from FIG. 3.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

[0013] In the specification, the term “telematic device” or “clientdevice” refers to a device which is generally equipped to receive,process and output information or the like to another device or a user.Historically, telematic devices receive and process digital dataincluding sound, textual and graphic data as, for example, filetransfer, electronic mail, facsimiles, electronic posts, data bankaccess, information center access, images, instructions and multimediafiles. While early telematic devices operated in a wired network, manycurrent devices receive data over a wireless network. It should beunderstood that the present invention contemplates telematic devicesthat receive data transmitted over a wireless network. Such devices andwireless networks are known in the art.

[0014]FIG. 1 is a block diagram generally depicting elements of anembodiment of the present navigation system. The system includes aclient device 10 located in a vehicle 8. The client device 10 is atelematic unit that has the capability to transmit signals 32 andreceive signals 30 through a wireless communication network orinfrastructure 34 as well as several elements described in more detailbelow. A wireless gateway 36 directs signals to and from the wirelessinfrastructure 34 to a service center 45. The service center 45 includesa navigation server 40 and a service center workstation 50 and a deviceto transmit both data and voice information from the navigation serverand workstation. The navigation server includes map and directionalinformation. A human operator can operate the workstation 50, which isconnected to the navigation server. The navigation server 40 may beaccessible, preferably through Internet connection, by a user's webbrowser 60, so that the user may set route preferences, store commondestinations and plan trips.

[0015] A vehicle client device 10 is located in the vehicle 8 (generallydepicted by the dashed lines at reference character 8). As shown in moredetail in FIG. 2, the client device 10 includes a voice command andcontrol system 12. The voice command and control system 12 providesautomatic voice recognition of voice communication from the user. Thevoice command and control system 12 processes voice communications todetermine whether a spoken word or speech pattern matches any of thestored grammars or vocabulary. When the system 12 identifies a speechpattern, the system sends an output signal to implement the specificfunction associated with the specific pattern to the audio decoding andplayback portion 14. Many or all of the functions capable of beingeffected by the voice command system 12 are capable of being controlledby control buttons 18 on the client device.

[0016] The client device 12 may include an audio decoding and playbackportion 14. The audio decoding and playback unit 14 receives and storesdigital information sent through the wireless infrastructure 34 from thenavigation server 40. Audio information is decoded from the digitalformat and played back or outputted to a speaker in the client device 10or the vehicle audio system or the like. The unit 14 may containcomputer readable program code that plays the decoded information in astepwise fashion in response to commands from the voice command andcontrol system 10 or the control buttons 18 or a positioning system 20.It should be understood that the information stored in the client device10 received from the service center 45 may contain textual informationand other visual or graphic information. The textual information andother graphic information can be played in a stepwise fashion coincidingwith the audio information. Graphic information, including textualinformation is displayed by the head unit display 16. The presentinvention includes the transmission of geocoded information, such asimages, maps or pictograms. Also geocoded information may form a portionof the transmitted information including road-links and geographicproperties or attributes such as latitude, longitude, house numbers orpoints of interest.

[0017] One embodiment of the present invention includes the retrieval ofmap information from the navigation server and providing drivinginstructions therefrom. The driving instructions, whether audio, textualor both, are assembled into discreet steps or sequential steps bycomputer readable program code in the navigation server 40. Each steprepresents a single navigational event such as “Turn west on Highway 66and proceed for five miles.” Each step is separated or identified by akeyword, symbol or indicator that the client device is designed torecognize as the end of an instructional step and the beginning of thenext step. In this manner, the playback portion 14 of the client device10 recognizes where to stop and begin playback of the storedinstructions. In another words, the navigational information is storedin the client device with inserted indicators that act as pauseindicators. The pause indicators are recognized by computer readableprogram code in the client device to trigger the playback portion of theclient device to pause. Thus, after storing the instructions in the datastorage portion 14 of the client device 10, the playback portion 14responds to commands given by the user by playing back a portion of thedriving instructions until a pause indicator is reached. Further,commands produce sequential stepwise playback of the instructions. Thus,the stepwise playback of navigational events involves recognition of apause indicator, pausing the playback function, recognizing a command toproceed, replay (or other command) and playing the appropriatenavigational step in response to the type of command.

[0018] The client device 10 includes a positioning system 20. In oneembodiment, the positioning system 20 is a Global Positioning System(GPS). As discussed above, a GPS is used to determine a vehicle'sposition in the positioning system 20 as is known in the art. Thepositioning system 20 both determines the present position of thevehicle and transmits 32 the computed position to the service center 45via the wireless infrastructure 34 through the cellular voice and datanetwork access device 22. The cellular voice and data network accessdevice 22 may be an imbedded cell phone and uses wireless communicationsstandards such as AMPS, TDMA, CDMA, GSM, etc., in order to establish avoice and data connection through the wireless infrastructure and thewireless gateway 36 to the service center 45. The cellular voice anddata network access device is well known in the art.

[0019] The wireless gateway 36 connects the wireless infrastructure tothe service center 45. The service center 45 includes the navigationserver 40 and the service center workstation 50. The navigation server40 includes a database or storage device with map and directioninformation. The stored information may be updated to reflect currentroad and driving conditions. The update may be done automatically byreal time connection to weather and traffic nodes via the Internet orsimilar connection. Updating or maintenance may also be performed bysystem administrators who input road and traffic conditions, and amendroutes in view of construction and so on.

[0020] The user's web browser 60 may be used to access the navigationserver 40 through the Internet. The navigation server 40 can provideuser accessible password protected access through which the user may setroute preferences, store common destinations and plan trips. When theuser requests calculation of a route, the navigation server can accessthe user's preferences and compare the requested route to the storedpreferences. In this manner, the server 40 supplies routes that areinput and preferred by the user.

[0021] FIGS. 3-4 illustrate the method of operation of one embodiment ofthe present system, and also refer to aspects and elements of theinvention shown in FIGS. 1 and 2. Referring to FIG. 3, the customer oruser initiates the service 70 by using a push-to-talk button or the likelocated on the client device 10 located in the vehicle 8. The customerstarts the service through the voice command and control 12 interface byspeaking “Directions” after a voice prompt. The client device 10 cansend a number of messages 72 including a “Call in Progress” message 74to the head unit 16 to notify the user that the system is initiatingcontact with the service center 45. The client device also sends amessage 78 to the service center 45 which includes one or more of theclient device 10 position (using data obtained from the GPS unit 20),identification and type of call (i.e., a request for directions). Theclient device 10 also establishes a voice call 76 to the service center45. Both the message 78 and the voice call 76 are sent by way of thecellular voice and data network access device 22 located in the clientdevice 10.

[0022] The system determines whether the client device 10 is subscribedor authorized for service 80. Either the client device 10 or the servicecenter 45 may accomplish the determination. The service center 45recognizes the call as a request for directions and routes 82 the callto the next available service representative at a service centerworkstation 50. When the call is routed 82 to a service representativethe system sends information regarding the type of call, the location ofthe client device 10 and the identification of the subscriber to theservice center workstation 50. When the voice call becomes active theclient device 10 sends a “Call Active” message 84 to the head unit 16.This notifies the vehicle user that the voice call is connected to aservice representative. The client device 10 mutes 86 the audio system,i.e., the radio, tape player, CD player or the like.

[0023] Through the voice connection, the service representative requeststhe current location 88 of the vehicle to validate that the locationgiven by the positioning system 20 is accurate and compares the verballocation with the location given by the positioning system 20. The userrequests that the service representative calculate a route to a givendestination 90. The service representative enters the destination 92into the service center workstation 50 and requests that the uservalidate the destination. The service representative advises the userthat the route will be calculated and downloaded to the client device10. In an alternate embodiment (not shown), the requested destinationmay be input by keying a phone number with a keypad, or selecting aphone number, which characterizes the destination address. Thedestination information may be input from a portable computing device(PDA, Laptop) via a local wireless link.

[0024] The voice call is terminated 94 and the audio system is un-muted96 so that the voice command and control system 12 becomes active. Theservice representative initiates route calculation 98 at the servicecenter 45, which performs the task of calculating the route andinserting pause markers or indicators where necessary between thenavigational steps and transmits the route 100 to the client device 10.While the transmission of the route takes place, the client device 10sends a “Download in Progress” message 102 to the head unit 16 to informthe user that the route is being downloaded. The route is stored 104 inthe client device 10 in the data storage portion 14 and the dataconnection is terminated. The client device 10 sends a “Download isComplete” message 108 to the head unit 16 to inform the user that theroute is stored in the client device and is available for playback. Atapproximately the same time, the service center creates a service record106.

[0025] Steps 110-118 involve the playback of the navigationalinstructions and are performed as a loop until the user arrives at thefinal destination. After the download is complete, the client device 110mutes the audio system to prevent accidental triggering of the commandsystem and provides for the input of commands by the user.

[0026] In one embodiment, the commands are voice commands made by theuser, which as detailed above are interpreted by the voice command andcontrol system. The client device 10 un-mutes 114 the audio system andin response to a command 112, plays 116 the appropriate navigationalstep. Triggering playback and/or display of the navigational steps 116outputs the downloaded media in one or more of audio, textual andgraphic forms. In other words, the information is played/and ordisplayed to the user as audible instructions, textual instructions,graphical symbols, pictograms, images or the like by the client device10. The commands contemplated for effecting playback of a navigationalstep include, but are not limited to: NEXT, PREVIOUS, SAY AGAIN, REPEAT,STOP, and CONTINUE.

[0027] In another embodiment, the commands are input by the useractuating control buttons 18 or the like on the client device 10. Thecontrol buttons have similar designations as the verbal commands.

[0028] In yet another embodiment, the commands to effect playback of thenext navigational step are signals from the positioning system 20. Themethod of triggering voice based route guidance based on signals from aposition detector (GPS) is well known in the art.

[0029] When the vehicle plays back the last navigational step 118, theclient device 10 sends a status message 120 to the head unit 16.

[0030] The present invention may be embodied in other specific formswithout departing from its spirit or essential characteristics. Thedescribed embodiments are to be considered in all respects only asillustrative and not restrictive.

We claim:
 1. A method of operating a navigation system for a vehiclecomprising: determining an initial position of the vehicle; initiating arequest for service, the request including transmission of the initialposition of the vehicle; establishing a voice connection, the voiceconnection providing transmission of a desired position of the vehicle;calculating a route for the vehicle from the initial position to thedesired position; transmitting the calculated route to the vehicle in amedia format adapted to be provided in a stepwise sequential fashion inresponse to commands.
 2. The method of operating the navigation systemof claim 1 wherein at least one of playing and displaying the calculatedroute in the stepwise sequential fashion takes place in response to thecommands.
 3. The method of operating the navigation system of claim 2wherein the commands are verbal commands from an occupant of thevehicle.
 4. The method of operating the navigation system of claim 2wherein the commands are generated by actuating buttons.
 5. The methodof operating the navigation system of claim 2 wherein the commands aregenerated by a positioning device.
 6. The method of operating thenavigation system of claim 1 wherein the request includes theidentification of the vehicle.
 7. The method of operating the navigationsystem of claim 6 wherein the request including the identification ofthe vehicle is used to validate that the vehicle is a current subscriberfor the navigation system.
 8. The method of operating the navigationsystem of claim 1 wherein the media format includes audio information.9. The method of operating the navigation system of claim 1 wherein themedia format includes textual information.
 10. The method of operatingthe navigation system of claim 1 wherein the media format includesgeographic properties.
 11. The method of operating the navigation systemof claim 1 wherein a service record is created when the transmittal ofthe route is complete.
 12. A navigation system for a vehicle forproviding navigational instructions to a user comprising: positioningdetermining means for determining an initial position of the vehicle;initiating means for initiating a request for service, the requestincluding transmission of the initial position of the vehicle;establishing means for establishing a voice call, said voice callincluding providing a desired position of the vehicle; route calculationmeans for calculating a route for the vehicle from the initial positionto the desired position; and transmitting means for transmitting theformatted calculated route to the vehicle in a media format adapted tobe provided in stepwise fashion in response to commands.
 13. Thenavigation system of claim 12 further comprising: formatting means forformatting the calculated route into a format adapted to be provided ina stepwise sequential fashion; transmitting means for transmitting theformatted calculated route to the vehicle; receiving means for receivingthe formatted calculated route in the vehicle; storage means for storingthe formatted calculated route; command and control means forcontrolling playback of the stored formatted calculated route; decodingmeans for decoding the formatted calculated route into at least one ofvoice, textual, and graphic data; output means responsive to the commandand control means for outputting the decoded data; and at least one ofdisplay and playback means for displaying and playing the output fromthe output means in the stepwise sequential fashion.
 14. The navigationsystem of claim 12 wherein the data stored in the storage means of theclient device is adapted to be output in a stepwise manner in responseto commands from the command and control means.
 15. The navigationsystem of claim 12 wherein the route calculation means and theformatting means are included in a service center, the service centerfurther comprising a navigation server and associated workstations, thenavigation server including a computer storage device having mapinformation and a database for storing user information, theworkstations being connected to the navigation server to provide accessto the map information and user information, and the service centerincluding communication means for communicating data and voiceinformation to and from the vehicle.
 16. Computer usable media storing aprogram in a navigation system for a vehicle comprising: computerreadable program code that receives navigating instructions in at leastone of an audio, a textual and a graphic media, formats the instructionsinto discreet steps; and computer readable program code that receivesand stores the formatted instructions and outputs the instructions to anassociated output device in a stepwise fashion in response to commands.